Explosive shell having contact fuse detonated by shearing of flange on fuse body



Dec. 26,

H. BEDALL EXPLOSIVE SHELL HAVING CONTACT FUSE DETONATED BY SHEARING Filed July 12, 1965 OF FLANGE ON FUSE BODY 2 Sheets-Sheet 1 smw/ I l mi MH will INVENTOR HANS BEDALL 3,359,901 l EXPLosIvE SHELL HAVING CONTACT FUSE DETONATED BY SHE/mmc Dec. 26, 1967 H. BEDALL OF FLANGE ON FUSE BODY 2 Sheets-Sheet 2 Filed July 12, 1965 FIG. 5

INVENTOR HANS BEDALL United States Patent O 3,359,901 EXPLOSIVE SHELL HAVING CONTACT FUSE DETONATED BY SHEARING OF FLANGE ON FUSE BODY Hans Bedall, Nuremburg, Germany, assignor to Diehl, Nuremberg, Germany Filed July 12, 1965, Ser. No. 471,086 Claims priority, application Germany, July 14, 1964, D 44,936; July 25, 1964, D 45,043 3 Claims. (Cl. 102-73) ABSTRACT F THE DISCLOSURE Contact fuse arrangement in which the fuse has a cylindrical casing in a cylindrical cavity in the shell end with a shearable flange on the casing engaging the nose end of the shell and with the nose end of the casing having a sharp edge to dig into an object upon oblique contact of the shell with the object.

The present invention relates to an rarrangement of a contact or percussion fuse or an inertia fuse in easily deformable shells as, for instance, hollow charge shells and the like in which the fuse is varranged in the head or nose of the shell. The invention is furthermore concerned with the design of such fuses.

The time required for igniting a bursting charge by means of a contact or inertia fuse amounts to approximately 5 10-5 seconds, counting from the moment when the shell hits the target up to the ignition of the charge. With an impact speed of 300 meters per second, this time period corresponds to a ight distance of millimeters. Thus, the shell ies upon impact 15 millimeters further in the direction of flight of the shell prior to the ignition of the charge, while, for instance, a sheet metal hood or the like provided on the front end of the shell is pressed in 0r battered. This distance is suicient for many shells, especially hollow charge shells, not only to jam the fuse but above all to considerably impair the electiveness of the hollow charge.

An inertia fuse, to become eifective, requires not only a retardation or braking of a defined minimum value but in addition thereto, only a limited deviation in the angle of impact is permissible. For pur-poses of producing the required force component in axial direction of the shell, in case of an impact under an extremely acute angle, a nonpermissible strong deformation of the shell occurs which, in turn, harmfully affects the effectiveness of the shell to a considerable extent.

It is, therefore, an object of the present invention to provide a fuse for easily deformable shell bodies, which will overcome the above-mentioned drawbacks.

It is a further object of the present invention to provide a contact or inertia fuse and to arrange the same in a shell in such a way that la battering or damaging of the shell or its front cover, is prevented up to the ignition of the charge.

It is a still further object of the present invention to make possible the employment of inertia fuses in easily deformable shells as, for instance, hollow charge shells.

It is another object of the present invention to provide a fuse having a penetrable head plate with an additional device serving as impact amplifier and assuring a reliable and fast actuation of the fuse even in case of an impact under an extremely acute angle or in case of an impact from the side.

These and other objects and advantages of the invention will appear more clearly from the following specilication in connection with the accompanying drawings, in which:

FIGURE l is a side View of a hollow charge shell hav- 3,359,901 Patented Dec. 26, 1967 ICC ing its head or nose provided with 'a fuse according to the present invention;

FIGURE 2 shows in section the top portion .of FIG- URE l on a larger scale than that of FIGURE l;

FIGURE 3 illustrates a partial section through a contact or percussi-on fuse with an impact amplifying device according to the present invention;

FIGURE 4 shows a longitudinal section through an inertia fuse according to the present invention;

FIGURE 5 illustrates a safety device for use in connection with the fuse according to FIGURE 4.

The arrangement according to the present invention is characterized prirnarly in that the fuse is axially displaceably guided in the head or nose portion of the shell and held in such a way that in the starting position, upon tiring, it protrudes beyond the head of the shell by a distance corresponding at least to the time period required from the impact of the head plate upon the target up to the ignition of the charge of the shell. The fuse is held in its protruding position up to the impact upon the target by a member adapted to be sheared off. According to one feature of the present invention, the contact fuse or especially the inertia fuse may be inserted in la central tube of the shell or shell cap without the intervention of a thread and may rest with an annular collar against the end face of the tube serving as shearing ring.

For purposes of amplifying the eifect of the impact, especially in case of an impact under small acute angles, the head plate which is adapted to be pressed in or which is arranged on the fuse body so as to be displaceable in transverse or inclined direction, may enc-ase a priming cap by means or a recess, while the priming cap is provided with an ogivally caved-out charge sitting on a priming anvil of the fuse body. Bores provided in the anvil extend into a channel leading to the priming means of the fuse.

According to a further feature of the present invention, a preferably crowned body of tough and elastic synthetic material may be provided in the head of the shell and serve as a protective member.

According to a still further feature of the present invention, there may be provided a safety device permitting a safe transport of the shell. This safety device Imay be designed as a resilient clamp with a pin extending into the range of displacement of the inertia body of the fuse while an elastic ring surrounding the pin lserves as a seal for the bores of the fuse provided for the introduction of the pin.

Referring now to the drawings in detail, FIG. l shows a hollow charge shell 1 with a sheet metal hood 2, while a fuse 3 protrudes from the top portion of said hood. As more clearly shown in FIG. 2, hood 2 is provided with a centrically arranged tube 4 protruding beyond the end portion of hood 2. A -fuse body 3 is pressed into the tube 4, said fuse body being of cylindrical outer shape and provided with a percussion cap or primer 5. Fuse body 3 has arranged thereon an annular collar 6 resting against the end face 0f tube 4. The front end of fuse body 3 is provided with a at plate 7. The cylindrical portion 8 of fuse body 3 which is located in front of collar 6 when looking in the firing direction of said shell is preferably smaller' in diameter than the portion 8a behind collar 6, portion 8a frictionally engaging the inner wall of tube 4.

As shown in FIG. 3, head plate 7 is flanged or beaded in a thin-wallfai portion 10 of a fuse head portion 9. Within fuse body 3 there is arranged a priming or ignition mechanism known per se, as shown, for instance, in greater detail in FIG. 4, in FIG. 3 only a back-firing sleeve 11 being shown. A liring pin or percussion needle .12 is provided with a head 13 designed as piston and guided in a cylinder 14 of head portion `9. Firing pin or percussion needle 12 is through the intervention of -a disk 15 held in the position shown in FIG. 3 by means of a helical pressure spring 16 surrounding needle 12.. Piston 13 is axially displaceably guided in Cylinder 14. In a widened bore 17 of head portion 9 there is provided a primer anvil 18, a bore 1% of which leads into lcylinder 14. Anvil 18 has placed thereover a priming cap 20 which is lled with a priming charge 21 corresponding to the shape of anvil 18 and hollowed or carved out so as to be of ogival shape. Head plate 7 encases priming cap 20 from the outside by means of a cup-'shaped recess 22 provided in a conical extension 23 of head plate 7.

According to the embodiment shown in FIG. 4, the fuse is inserted into the head of a shell designed as cylindrical tube 4. The fuse comprises a cylindrical tube 3 the outer diameter of which is so selected that it is insertable into and frictionally engages tube 4, and furthermore comprises a collar 6 resting against the end of tube 4. The interior of tube 3 has inserted therein an inertia fuse mechanism known per se, which comprises a percussion cap or primer which is by means of a threaded ring 2.4 screwed into an axially displaceable inertia body 25. Body 25 is guided in tube 3 while its axial movement is limited in rearward direction by an abutment ring 26. Body 25 is centrically screwed into a guiding member 27 which has axially displaceably arranged thereon backiriug sleeve 11 while percussion needle 12 extends through a central bore in guiding member 27. Between body 25 and an enlarged collar 28 of sleeve 11 there is provided a helical pressure spring 29 which in its rest position presses body 25 against abutment ring 26 and also presses sleeve 11 toward the front (in firing direction of the shell) against an enlarged collar 30 in guiding member 27.

Sleeve 11 has provided therein a band-shaped woundup butler spring 31 which rests on collar 30. Similar to the arrangement according to FIG. 3, a helical pressure spring 16 is provided between guiding member 27 and dislt which is coupled with percussion needle 12. Spring 16 presses disk 15 against head portion 32 which is screwed into the front portion of fuse body 3, while the upper end of needle 12 protrudes into a recess 33 of head portion 32. Head portion 32 has an approximately cylindrical outer shape and has its front side (when looking in firing direction) provided with a conical recess 34 merging into a cylindrical recess 35. In this way head portion 32 forms a sharp-edged rim 36 which assures a reliable gripping effect and thereby a reaction of the fuse already at acute impact angles of approximately 15 to 20. Recesses 34 and 35 have pressed thereinto a body 37 consisting of elastic synthetic material, for instance polyethylene, and provided with a -crowned surface 38, a stepped shank 39 and a cylindrical clamping plug 40. Body 37 on one hand prevents injury at the sharp-edged margin of rirn 36 and on the other hand serves as protection during a perpendicular fall of the shell onto its tip up to 1.5 meters.

For purposes of improving the ballistics of the shell there is furthermore provided a coat or cover 41, preferably of somewhat brittle material, and extending around the head portion 32. The rearward portion of cover 41, i.e. that portion which extends towards fuse body 3, approximately has the same diameter as collar 6, whereas its front portion tapers towards body 37. A small extension 42 at head portion 32 prevents an undesired sliding of cover 41 in forward direction.

In order to assure a safe transport of the fuse, tube 4 ot' the shell and fuse body 3 are provided with one lateral bore 43 each, the two bores 43 being in axial alignment with each other. A pin 44 is adapted to be passed through these bores and is adapted to extend into the range of displacement of collar 28 at sleeve 11. Pin 44 is riveted to a resilient clamp 45 adapted to be inserted into an annular groove 46 of tube 4. A ring 47 of rubber or synthetic material and slipped on pin 44 seals bores 43 against penetration of water or steam and the like. As is more clearly shown in FIG. 5, clamp 45 is provided with radially aring ends 43 permitting a fast removal of the clamp from tube 4 and thereby a fast preparation of the shell for firing.

During firing, due to inertia of sleeve 11 during the acceleration phase, wound-up spring 31 is freed and will rest from the inside against fuse body 3 after it has been released by collar 30 during a rearward sliding movement of sleeve 11. When the shell impacts upon a target, inertia body 25 will, in view of the fast deceleration and braking of the fuse, move forwardly so that percussion needle 12 will pierce percussion cap 5. Furthermore, u-pon impact of head portion 32 fuse body 3 is pounded into tube 4. Thus, the annular end face of tube 4 will shear off collar 6 of fuse body 3 so that the entire fuse will be pushed into tube 4 without, however, deforming to any appreciable degree hood 2 which is connected to tube 4. Depending upon the impact speed of the shell and the speed of response of the charge, the possible movement of displacement of the fuse amounts to 20 millimeters or more. Coat or cover 41 is destroyed upon impact, for instance, is crushed.

The fuse according to FIG. 3 operates as Contact fuse in the following manner. When plate 7 impacts upon a target, for instance head-on or from the side, priming cap 2t) with priming charge 21 impacts upon anvil 18. The thus produced gas pressure acts upon piston 13 of needle 12 and propels the same toward the rear whereby it pierces percussion cap 5 in a manner similar to and with the same means as described and shown in FIG. 4.

It is, of course, to be understood that the present invention is, by no means, limited to the particular constructions shown in the drawings, but also comprises any modications within the scope of the appended claims.

What is claimed is:

1. A fuse structure for an easily deformable shell adapted for having an explosive charge therein, said shell having a bore in its nose end, a fuse casing in the said bore having a percussion cap operable when ignited to detonate said charge, and means in the casing operable upon impact of the shell against an object for igniting said percussion cap, said casing having a portion protruding from the nose end of said shell a distance substantially equal to the distance the shell will travel during the interval from said impact of the shell against an object up to ignition of said percussion cap, the outermost end of said casing having an axial bore therein with a ared mouth, a resilient member having a shank in said bore and a disc-like head tting said ared mouth and convex on the outer side, said fuse casing including an axially short shearable annular collar thereon engaging the nose end of the shell and which collar will shear off upon the impact of the shell against an object, said fuse casing closely ting said bore but being slidable inwardly in the bore upon impact of the shell against an object, and a sleeve of relatively brittle synthetic material surrounding said fuse 4casing forwardly of said collar and having one end resting on the collar and tapering inwardly from the collar end thereof to the other end thereof, Said casing having a rearwardly facing shoulder engaging the said other end of said sleeve.

2. A fuse structure for an easily deformable shell adapted for having an explosive charge therein, said shell having a bore in its nose end, a fuse casing in the said bore having a percussion cap operable when ignited to detonate said charge, and means in the casing operable upon impact of the shell against an object for igniting said percussion cap, said casing having a portion protruding from the nose end of said shell a distance substantially equal to the distance the shell will travel during the interval from said impact of the shell against an object up to ignition of said percussion cap, said fuse comprising a pin extending in the axial direction of the shell and spaced from said percussion cap, said pin and cap being moveable relatively in the axial direction of the shell to etfect engagement of the pin With the said percussion cap to ignite the same, said fuse casing having a relatively thin walled cylindrical nose end, a ldisc-like head plate seated in said nose end of the fuse casing, a shank portion on said head plate extending rearwardly therefrom and substantially smaller in diameter than the inside of said cylindrical nose end so the head plate can tilt if obliquely impacted, a recess in the inner end of said shank portion, a priming cap in said recess, an anvil on which the cap rests, the charge in said cap being shaped to embrace the end of said anvil, and a bore leading through said anvil and casing to the end of said pin opposite said percussion cap, said shaped charge insuring the primer cap will be red upon deformation of said nose end of said casing by direct or oblique impact, said pin being resiliently biased away from said percussion cap, a portion of said casing surrounding the end of said pin adjacent said anvil so the pin acts as a piston when said charge 6 is ignited and is driven by the discharge therefrom toward said percussion cap.

3. A fuse structure according to c'lairn 2 in which said head plate engages said nose end at the outer extremity only of said head plate.

References Cited UNlTED STATES PATENTS 1,706,802 3/1929 Methlin 102--73 2,359,317 10/1944 Landen 102-77 X 2,426,171 `8/ 1947 Alverson 102-8l.6 2,601,827 7/1952 Brandt 102-73 2,892,411 6/ 1959 Brown et al 102--70.2 3,119,338 1/1964 Pissacroia IGZ-86.5 X

BENJAMIN A. BORCHELT, Primary Examiner.

G. H. GLANZMAN, Assistant Examiner. 

1. A FUSE STRUCTURE FOR AN EASILY DEFORMABLE SHELL ADAPTED FOR HAVING AN EXPLOSIVE CHARGE THEREIN, SAID SHELL HAVING A BORE IN ITS NOSE END, A FUSE CASING IN THE SAID BORE HAVING A PERCUSSION CAP OPERABLE WHEN IGNITED TO DETONATE SAID CHARGE, AND MEANS IN THE CASING OPERABLE UPON IMPACT OF THE SHELL AGAINST AN OBJECT FOR IGNITING SAID PERCUSSION CAP, SAID CASING HAVING A PORTION PROTRUDING FROM THE NOSE END OF SAID SHELL A DISTANCE SUBSTANTIALLY EQUAL TO THE DISTANCE THE SHELL WILL TRAVEL DURING THE INTERVAL FROM SAID IMPACT OF THE SHELL AGAINST AN OBJECT UP TO IGNITION OF SAID PERCUSSION CAP, THE OUTERMOST END OF SAID CASING HAVING AN AXIAL BORE THEREIN WITH A FLARED MOUTH, A RESILIENT MEMBER HAVING A SHANK IN SAID BORE AND A DISC-LIKE HEAD FITTING SAID FLARED MOUTH AND CONVEX ON THE OUTER SIDE, SAID FUSE CASING INCLUDING AN AXIALLY SHORT SHEARABLE ANNULAR COLLAR THEREON ENGAGING THE NOSE END OF THE SHELL AND WHICH COLLAR WILL SHEAR OFF UPON THE IMPACT OF THE SHELL AGAINST AN OBJECT, SAID FUSE CASING 